APPEARANCE: Ao bōzu are generally depicted as large, one-eyed, blue-skinned priests with a strong connection to magic. However, local accounts vary greatly in details such as size, number of eyes, and habitat. In Okayama, they are described as two-eyed giants who take up residence in abandoned or uninhabited homes. In other stories, they appear in wheat fields, or on dark, lonely roads.

INTERACTIONS: In Shizuoka, ao bōzu are said to appear on spring evenings at sunset in the wheat and barley fields. The transition from night to day is a popular theme in the tradition of in-yō sorcery. Further, the still blue-green leaves of the young barley also have powerful connections to in-yō. Children who go running and playing through the fields in the evening might be snatched up and taken away by an ao bōzu. Thus, good children must go straight home after school and not go tramping through the fields!

In Kagawa, ao bōzu appear late at night to young women and ask them, “Would you like to hang by your neck?” If the woman says no, the ao bōzu disappears without a word. However, if she ignores him or says nothing, he attacks her with lightning speed, knocks her out, and hangs her by the neck.

In Yamaguchi, they are considered minor deities. They appear before humans on the road and challenge them to sumo matches. Because Yamaguchi’s ao bōzu are only as big as children, many a person has foolishly accepted the challenge, only to find himself flung to the ground with god-like strength and potentially lethal speed.

ORIGIN: Very little is known about this yokai. Toriyama Sekien was the first to record the ao bōzu, and his illustration came with not a single word of description other than its name. From its name, we can glean a little bit of information; the word ao means blue or green, and can denote immaturity and inexperience. (Another well-known yokai — ao-nyōbō — uses this color in a similar manner.) As the original illustration was black-and-white, it may even be that this yokai was never intended to be colored blue or green, but rather just as a mockery of what Toriyama Sekien saw as a corrupt and unskilled priesthood. Nonetheless, thanks to its name, it is usually depicted in a sickly shade of ao.

The fact that ao bōzu has only one eye and is revered as a minor god in some places draws a strong parallel with another yokai, the hitotsume-kozō. Because of his similarity, there are theories suggesting a connection to the ancient spirit worship of old Japan. In these shamanistic proto-religions, one-eyed monsters often originated as fallen mountain gods and bringers of evil, sent to do the bidding of larger deities. They could be kept at bay with woven baskets, or other objects with many holes, which the monsters would view as hundreds of eyes and avoid, either out of fear or jealousy.

Because there are so many different accounts, and because there are so many different kinds of nasty priest yokai, it’s impossible to tell which, if any, is the real ao bōzu, and which are variations of other kinds of yokai.